On The Age Of Information In Status Update Systems With Packet Management

摘要

We consider a communication system in which status updates arrive at a sourcenode, and should be transmitted through a network to the intended destinationnode. The status updates are samples of a random process under observation,transmitted as packets, which also contain the time stamp to identify when thesample was generated. The age of the information available to the destinationnode is the time elapsed since the last received update was generated. In thispaper, we model the source-destination link using queuing theory, and we assumethat the time it takes to successfully transmit a packet to the destination isan exponentially distributed service time. We analyze the age of information inthe case that the source node has the capability to manage the arrivingsamples, possibly discarding packets in order to avoid wasting networkresources with the transmission of stale information. In addition tocharacterizing the average age, we propose a new metric, called peak age, whichprovides information about the maximum value of the age, achieved immediatelybefore receiving an update.